soil metagenome

A total of 14 treatments were conducted in this experiment: the farmland with continuous planting of cotton for 1 year, 3 years, 5 years, 8 years, 10 years, 15 years and 20 years in two sites (Aksu and Shihezi), named AKS1, AKS3, AKS5, AKS8, AKS10, AKS15, AKS20, SHZ1, SHZ3, SHZ5, SHZ8, SHZ10, SHZ15 and SHZ20, respectively. Soil samples were collected with a soil auger (2.5 cm in diameter, 0-20 cm deep) using the five-point sampling method, and five soil samples collected in each block were pooled into one sample, with 6 mixed samples per treatment.